 No power to fuel pump, seems to be a common problem around here |
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| warrenoliver |
 May 24 2013, 10:04 PM
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Member  Group: Members Posts: 363 Joined: 11-November 06 From: McFarland, Wisconsin Member No.: 7,199 Region Association: Upper MidWest  |
Car stalled on me this morning. When I tried to restart, the fuel pump would not turn on so no luck with the start. Towed it home and checked it out. It is a 73 2.0 with FI.
The pump runs when I jumper directly to the battery. I have continuity from pump connector to the #13 pin on the relay board. If I jumper from the fuse to the #13 pin, the pump comes on. The fuse is good. I have replaced the main power relay and the fuel pump relay with known good ones. With the ignition on, when I remove and reseat the main power relay, I can feel the relay click but I do not hear the injectors click nor do I hear the fuel pump start (I got this test from Dr. 914's Tech Tips). On the fuel pump relay socket, I have power at the 30 pin and also the 85 pin. When I jumper to the 87, it does not turn on the fuel pump. I don't know if it is related, but I have the same problem with the heater blower relay also. I jumpered 30 to 87 and I do not have power. I am not sure but I think the car died when I had the heater blower running. I'm stumped. What do I check next? |
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| Tom |
May 27 2013, 09:45 AM
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Advanced Member Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None |
Warren,
Take another look. Follow the lines from the power relay from the relay off of the board over to the socket connection. You are probably thinking the dotted lines go to the power relay. Follow the trace from pin #12 (14 pin connector), it goes up and over the trace for pin #14, then down to pin #30 of the power relay. Now look at pin #14 and trace it back to the fuse connection on the right side. From the left side of the fuse (This could be where there is a bad connection) the trace goes to pin #30 for the rear window heater relay and then down to the pin #30 for the fuel pump relay, and finally down to the heater blower. The fuse is the common point for power transfer for all of these relays except the power relay. I would not be surprised if your fuse holder has a bad connection to the traces on the relay board, probably on the top side where it gets exposure to humidity. That is where I had to repair mine. Tom |
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Posts in this topic
warrenoliver No power to fuel pump May 24 2013, 10:04 PM
Tom Jumpering pin 87 of the fuel pump relay is the sam... May 25 2013, 03:46 AM
warrenoliver Tom,
When I jumper from the fuse to 87 of the fue... May 25 2013, 07:17 AM warrenoliver I tested the heater fan circuit also. The fan run... May 25 2013, 08:00 AM warrenoliver I spread the pins on the relays and cleaned the co... May 25 2013, 08:37 AM Dave_Darling Both the heater fan blower and the fuel pump relay... May 25 2013, 08:45 AM warrenoliver Thanks Dave,
The relays are good. When i have the... May 25 2013, 09:37 AM Dave_Darling
When i have the power supply relay in, and the ke... May 26 2013, 11:26 AM Jon H. Do you still hear the clicking coming from the TPS... May 25 2013, 04:20 AM Cap'n Krusty Install the 2 headlight motor relays in the FI con... May 25 2013, 07:36 AM warrenoliver I tried that previously but I just tried it again ... May 25 2013, 09:23 AM 76-914 . Here ya go http://members.rennlist.com/... May 25 2013, 08:09 AM warrenoliver Thanks for the Anders troubleshooting tips. When ... May 25 2013, 09:43 AM Bob L.
Thanks for the Anders troubleshooting tips. When... May 25 2013, 10:26 AM warrenoliver OMG, thanks Dave for the pictures. Without those,... May 25 2013, 12:17 PM Bob L.
OMG, thanks Dave for the pictures. Without those... May 25 2013, 12:50 PM warrenoliver Oops, sorry! Thanks Bob.
May 25 2013, 02:52 PM Tom Warren,
Sorry to not answer back sooner. I have... May 25 2013, 03:39 PM warrenoliver Tom,
I think you may be right but I just don... May 25 2013, 04:42 PM Tom Warren,
From what you have said, it doesn't... May 25 2013, 04:59 PM warrenoliver Tom,
I unplugged the AAR and it didn't help.
... May 25 2013, 07:00 PM Jon H. Don't forget, he is also not hearing the injec... May 25 2013, 05:22 PM warrenoliver I can hear clicking when I reseat the relays but I... May 25 2013, 06:42 PM Jon H.
I can hear clicking when I reseat the relays but ... May 25 2013, 07:02 PM warrenoliver Yes, when I jumper from the fuse to the 86 socket ... May 25 2013, 07:21 PM Jon H.
Yes, when I jumper from the fuse to the 86 socket... May 25 2013, 07:52 PM warrenoliver Thanks for all your help guys. Anyone know where I... May 25 2013, 07:55 PM Jon H.
Thanks for all your help guys. Anyone know where ... May 26 2013, 05:55 AM Tom Warren,
That could very well be the problem. ... May 25 2013, 07:47 PM Tom Warren,
I agree, you are getting very close to ... May 26 2013, 12:24 PM warrenoliver Some great ideas there Tom. I really appreciate e... May 26 2013, 03:31 PM jk76.914
Warren,
I agree, you are getting very close to... May 17 2015, 05:23 PM Tom Warren,
The #30 pin for the two relays are from... May 26 2013, 05:03 PM warrenoliver I must be missing something then. When i look at ... May 27 2013, 09:05 AM warrenoliver Tom,
Aha! I think you may be on to it. Even... May 27 2013, 12:22 PM warrenoliver DAMN!!!!!! This thing is... May 27 2013, 03:36 PM warrenoliver I think I have finally tracked it down. With the ... May 27 2013, 07:28 PM Jon H. I find these electrical Gremlins to be the most fr... May 28 2013, 04:17 AM Tom Warren,
Very happy I could help. Glad things ... May 28 2013, 10:56 AM revhi109 I am also having issues with my fuel pump not comi... Mar 30 2015, 10:12 AM warrenoliver
I am also having issues with my fuel pump not com... Apr 1 2015, 07:20 PM flylarry If the relay works and a jumper between the fuse a... May 17 2015, 08:15 PM |
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